在linq中使用group by到sql

Question

我在组中有一个问题，链接到sql
首先我有这个表：

1. 客户：Id_client，nom，prenom，villeId
2. ville ：id_ville，nom

代码：

 justiceDataContext dbContext = new justiceDataContext();
        GridView1.DataSource = from client in dbContext.Client
                               join ville in dbContext.Commande
                               on client.villeId equals ville.Id_ville
                               group client by ville.nom into g
                               select new { City = g.Key, NumberOfClients = g.Count() };
        GridView1.DataBind();

我的目标是按城市（client）

获取ville的数量

谢谢

Answer 1

dbContext.Client
    .GroupBy(c => c.villeId)
    .Select(g => new {
        CityName = dbContext.Villes.Where(v => v.Id_ville == g.Key),
        NumberOfClient = g.Count()
    }).ToList();

另一种方法：

var result = dbContext.Villes
            .Join(dbContextClients, v => v.IdVille, c => c.IdVille, (v, c)  => new { client = c, ville = v })
            .GroupBy(j => j.ville.IdVille)
            .Select(g => new {
                VilleName = g.First().ville.Name,
                NumberOfClients = g.Count()
            }).ToList();